Bowl-cartridge filter having interlock mechanism and methods

ABSTRACT

A bowl-cartridge filter includes a filter cartridge and a bowl. The filter cartridge includes an interlock arrangement that is oriented to engage the filter bowl, when the filter cartridge is mounted in the filter bowl, and the bowl is rotated in a direction to remove the bowl-cartridge filter from a filter head. The filter bowl includes a cooperating interlock arrangement that engages the interlock arrangement on the filter cartridge. Example embodiments include cog arrangements, which include a plurality of projecting teeth. Various shapes for the teeth are possible, including house-shaped, truncated A-shaped, and pie wedged shape.

This application claims priority under 35 U.S.C. § 119(e) to provisionalapplication Ser. No. 60/280,786, filed Apr. 2, 2001. Application60/280,786 is incorporated by reference herein.

TECHNICAL FIELD

This disclosure concerns generally filters, in particular filters forcleaning fluid, such as liquids including oil, fuel, and hydraulics. Thedisclosure also concerns methods of construction, assembly, and use.

BACKGROUND OF THE INVENTION

Filters are commonly used in connection with lubrication systems andfuel systems for internal combustion engines, and hydraulic systems forheavy-duty equipment. Filters are also used in many types of liquidsystems. In these types of systems, the filter is changed periodically.One of the standard type of filters used in the art is a bowl-cartridgefilter.

All-cartridge filters typically include a reusable bowl holding areplaceable cartridge filter (filter element). Bowl-cartridge filtersare mounted onto a filter head, wherein liquid to be cleaned passesthrough the filter head, into the bowl, through the replaceablecartridge filter, outside of the bowl, and back into the filter head.After a period of use, the bowl-cartridge filter is removed from thefilter head, and the replaceable cartridge filter is removed from thereusable bowl. The old cartridge filter is discarded, and replaced witha new cartridge filter. The new cartridge filter is operably mountedinto the reusable bowl, to provide a refurbished bowl-cartridge filter.This refurbished bowl-cartridge filter, containing the new cartridgefilter, is than mounted onto the filter head.

SUMMARY

A bowl-cartridge filter is disclosed having a filter cartridge and abowl. The filter cartridge includes an interlock arrangement that isoriented to engage a filter bowl, when the filter cartridge is mountedin the filter bowl and the bowl is rotated in a direction to remove thebowl-cartridge filter from a filter head.

Preferably, the filter bowl includes a cooperating interlock arrangementthat engages the interlock arrangement on the filter cartridge.

Methods of servicing, use, and construction are provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of a bowl-cartridge filtersecured to a filter head, constructed according to principles of thisdisclosure;

FIG. 2 is an exploded, perspective view of the bowl-cartridge filterdepicted in FIG. 1;

FIG. 3 is a schematic, cross-sectional view of the bowl-cartridge filterdepicted in FIG. 1, but not secured to the filter head;

FIG. 4 is an exploded, perspective view of the cartridge filter depictedin FIGS. 2 and 3;

FIG. 5 is a schematic, cross-sectional view of the cartridge filterremoved from the filter bowl depicted in FIG. 3;

FIG. 5A is an end view of the filter cartridge depicted in FIGS. 4 and5;

FIG. 6 is a schematic, perspective, partially fragmented view of thefilter bowl depicted in FIGS. 1-3;

FIG. 7 is a top plan view of the filter bowl depicted in FIGS. 1-3;

FIG. 7A is a fragmented, enlarged, schematic, side elevational view ofthree of the teeth utilized in the filter bowl depicted in FIGS. 6-8,and as taken along the line 7A-7A of FIG. 7;

FIG. 8 is a schematic, cross-sectional view of the filter bowl takenalong the line 8-8 of FIG. 7;

FIG. 9 is a perspective view of an end cap utilized as part of thefilter cartridge depicted in FIGS. 2, 4, and 5;

FIG. 10 is a top plan view of the end cap depicted in FIG. 9;

FIG. 11 is a schematic, cross-sectional view of the end cap taken alongthe line 11-11 in FIG. 10;

FIG. 12 is a fragmented, enlarged, schematic, side elevational view ofthree of the teeth utilized in the end cap depicted in FIGS. 9-11;

FIG. 13 is a perspective view of an alternate embodiment of an end capthat may be utilized as part of the filter cartridge depicted in FIGS.2-5;

FIG. 14 is a top plan view of the end cap depicted in FIG. 13;

FIG. 15 is a side elevational view of the end cap depicted in FIGS. 13and 14;

FIG. 16 is a perspective view of another alternate end cap that may beutilized as part of the cartridge filter depicted in FIGS. 2-5;

FIG. 17 is a top plan view of the end cap depicted in FIG. 16;

FIG. 18 is a schematic, cross-sectional view of the end cap, thecross-section taken along the line 18-18 of FIG. 17;

FIG. 19 is an exploded, perspective view of the filter cartridgedepicted in FIGS. 2 and 3, but with the end cap shown in FIGS. 16-18;

FIG. 20 is a top plan view of an alternate embodiment of a filter bowlusable with the end cap of FIGS. 16-19;

FIG. 21 is a schematic, perspective, partially fragmented view of thefilter bowl depicted in FIG. 20;

FIG. 22 is an exploded, perspective view of another embodiment of acartridge filter constructed according to principles of this disclosure;

FIG. 23 is a top plan view of the cartridge filter depicted in FIG. 22when assembled;

FIG. 24 is a cross-sectional view of the cartridge filter depicted inFIGS. 22 and 23, the cross-section being taken along the line 24-24 ofFIG. 23;

FIG. 25 is a bottom plan view of the cartridge filter depicted in FIGS.22-24;

FIG. 26 is a schematic, enlarged, side elevational view of a portion ofthe end cap for the cartridge filter depicted in FIGS. 22-24;

FIG. 27 is a perspective view of the end cap utilized on the cartridgefilter depicted in FIGS. 22-25;

FIG. 28 is a perspective view of a filter bowl useable with the filtercartridge depicted in FIGS. 22-25;

FIG. 29 is a schematic, cross-sectional view of the filter bowl depictedin FIG. 28;

FIG. 30 is a top plan view of the filter bowl depicted in FIG. 28; and

FIG. 31 is a schematic, fragmented, enlarged side elevational view of aninside section of the filter bowl, the section being shown along line31-31 of FIG. 30.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A. Problems with Existing Arrangements

In a typical system that utilizes a bowl-cartridge filter, thebowl-cartridge filter is rotatably secured to a filter head. After aperiod of use, it will become necessary to service the bowl-cartridgefilter. This is done by removing the bowl-cartridge filter from thefilter head, and then removing the filter cartridge from the bowl. Thefilter cartridge is discarded and replaced with a new filter cartridge.The refurbished bowl-cartridge filter is then reattached to the filterhead.

When the bowl-cartridge filter is removed from the filter head, thecartridge filter may sometimes remain attached to the filter head. Whenthis happens, the fluid in the cartridge filter drips and spills intothe environment.

Improvements are desirable. Arrangements described herein help to reduceproblems associated with bowl-cartridge filters, such as the problemsdescribed above, and others.

B. The Arrangements of FIGS. 1-12

An example of an improved bowl-cartridge filter constructed according tothe present invention is illustrated in FIG. 1, in perspective view. Afiltration system 20 including a filter head 22 and a bowl-cartridgefilter 24 is illustrated. The bowl-cartridge filter 24 is shown as beingsecured to the filter head 22, usually in a manner that permits thebowl-cartridge filter 24 to be spun onto the filter head 22 or otherwiserotated and secured thereto. Typically, the bowl-cartridge filter 24 issecured to the filter head 22 by a threaded connection. The filter head22 may be constructed according to conventional, known filter heads; Ingeneral, the filter head 22 includes a liquid inlet port 26 and a liquidoutlet port 28. Liquid to be cleaned flows into the filter head 22through the inlet port 26, then into the bowl-cartridge filter where itpasses through filtration media to be cleaned, and finally flows in acleaned condition back into the filter head 22 and exists through theoutlet port 28.

Turning now to the bowl-cartridge filter 24, the assembly is shown inexploded, perspective view in FIG. 2. The illustrated bowl-cartridgefilter 24 includes a can or filter housing 30 holding or containingtherein a removable, replaceable, disposable filter cartridge 32. Thebowl-cartridge filter 24 also includes an inner liner, support, orcenter tube 34. In this particular arrangement, there is also a sealring 36.

From a review of FIGS. 1 and 2, it can be appreciated that the housing30 preferably includes a plurality of grooves 38 along an exteriorsurface 40 of the housing 30, to enhance the ease of gripping andmanipulation of the housing 30 relative to the filter head 22. It canalso be seen in FIG. 2 that the housing 30 includes a threaded region 42including a series of threads along an interior surface 46 to permit thefilter housing 30 to be threadably connected to the filter head 22 foroperable assembly.

A review of FIG. 2 illustrates some of the basic features of the filtercartridge 32. In general, the preferred filter cartridge 32 illustratedincludes an extension of filter media 48 extending between a first endcap 50 and a second end cap 52. The media 48 functions to inhibit thepassage of particulate matter in liquid flowing through it, in order toclean or purify the liquid passing through the bowl-cartridge filter 24.

The filter cartridge 32 and the bowl 30 cooperate with each other toensure that when the bowl 30 is rotated off of the filter head 22, thefilter cartridge 32 rotates with the bowl 30 and is also removed fromthe filter head 22. This cooperative relationship is explained in moredetail below.

Turning now to FIG. 3, a schematic, cross-sectional view of thebowl-cartridge filter 24 is depicted. As can be seen in FIG. 3, the bowl30 depicted is generally cylindrical in shape and defines an openinterior 54. The bowl 30 further includes a closed end 56 and an openend 58. In the one depicted in FIG. 3, the open end 58 is adjacent tothe threaded region 42. The open end 58 allows access into the openinterior 54, to permit the installation and removal of the filtercartridge 32 therein.

The seal ring 36 is preferably provided circumferentially lining theinterior surface 46 of the bowl 30 and provides a seal with the filterhead 22 in order to inhibit the leaking of liquid between the filterhead 22 and the bowl-cartridge filter 24.

In the preferred arrangement depicted, the second end cap 52 is adjacentto the closed end of the bowl 30. A seal ring 60 is preferably providedbetween the second end cap 52 and the interior surface 46 of the bowl 30to create a seal 62 therebetween and inhibit the passage of liquid froma dirty side to a clean side without passing through the media 48 first.

In the preferred embodiment depicted in FIG. 3, an o-ring 64 is mountedwithin the opening 66 defined by the first end cap 50. The o-ring 64creates a seal with the filter head 22 to inhibit the passage of liquidbetween a dirty side and a clean side without first passing through thefilter media 48.

In a forward flow system, liquid to be cleaned flows from the filterhead 22 and into an unfiltered liquid volume 68. In the one depicted inFIG. 3, the unfiltered liquid volume 68 is the volume of space betweenthe interior surface 46 of the bowl 30 and the filter media 48. Theliquid to be filtered then passes through the media 48, where thepassage of particles is inhibited and generally trapped. The liquid thenflows through the center tube 34 and then exits the bowl-cartridgefilter 24 and passes into the filter head 22. In a reverse-flow system,the liquid may pass first through the opening in the first end cap 50,into the center tube 34, through the filter media 48, into the volume 68(which would then be a filtered liquid volume), and then exit thebowl-cartridge filter 24 into the filter head 22.

In the one depicted in FIG. 3, this particular bowl 30 further includesan end plug 70 that aids in the draining of liquid from the bowl 30when-servicing the bowl-cartridge filter 24.

Preferably, the center tube 34 is a permanent, non-disposable member ofthe bowl-cartridge filter 24. In the preferred example depicted in FIG.3, the center tube 34 is secured to the bowl 30 at a projection 72 inthe bowl 30 by a press fit. The projection 72 is generally cylindricalin shape, having an outer annular surface 74. The center tube 34 engagesthe outer annular surface 74 and circumscribes it in a press fit manner.The press fit should be tight enough and secure enough to securelyfasten the center tube 34 to the bowl 30 and prevent the center tube 34from being removed from the bowl 30 when the filter cartridge 32 isremoved from the bowl 30.

FIG. 3 also depicts the bowl 30 and filter cartridge 32 engaged betweena cooperative interlock arrangement 80 that helps to ensure removal ofthe filter cartridge 32 from the filter head 22 at the same time thebowl 30 is removed from the filter head 22. This is detailed furtherbelow.

The particular filter cartridge 32 depicted also includes a secondregion of filter media 76 held by the second end cap 52, which helps toclean unfiltered liquid in the process of servicing the bowl-cartridgefilter 24. These features are characterized more fully in commonlyassigned, and co-pending U.S. Patent Application Ser. No. 60/280,787,filed on Apr. 2, 2001, and entitled “Filter Cartridge for a FilterAssembly”, incorporated herein by reference. With respect to theinterlock arrangement 80, no particular filter cartridge 32 ispreferred. The filter cartridge 32 depicted is merely one example, andin many instances, with respect to the interlock arrangement 80, willnot have the second region of media 76 or some of the other featuresfully characterized in Application Ser. No. 60/280,787.

Turning now to FIG. 4, the example filter cartridge 32 is depicted inexploded perspective view. In FIG. 5, the filter cartridge 32 with endcap 52 is depicted in schematic cross-section. As can be seen in FIGS. 4and 5, the depicted extension of media 48 is generally cylindricalhaving a first end 82, an opposite second end 84, and an open interiorvolume 86. The first end 82 is adjacent to and in contact with an innersurface 88 of the first end cap 50, while the second end 84 is adjacentto and in contact with an inner surface 90 of the second end cap 52. Inpreferred arrangements, the media 82 is made from cellulose, orsynthetic material, or a blend of the two. Other materials may be used,depending upon the particular system and application.

In preferred arrangements, the extension of media 48 is secured to thefirst and second end caps 50, 52 by, for example, bonding. In manypreferred arrangements, the media 48 is bonded to the first and secondend caps 50, 52 through either adhesive or urethane potting material.

In the particular filter cartridge 32 depicted in FIG. 5, the first endcap 50 includes a handle member 92. While a variety of structures may beprovided, the particular handle member 92 depicted includes: (i) aprojection 94 extending axially from a remaining portion 96 of the endcap 50; and, (ii) a circumferential rim 98 extending from the projection94. The projection 94 and rim 98 are preferably shaped and spaced fromthe remaining portion 96 to allow for the fingers of a person or,alternatively, tools to grasp the handle member 92 and remove the filtercartridge 32 from the bowl 30.

The filter cartridge 32 includes an interlock arrangement 100, whichforms part of the cooperative interlock arrangement 80 between thefilter cartridge 32 and bowl 30. In the preferred embodiment depicted,the cartridge interlock arrangement 100 extends from an outer surface102 of the second end cap 52.

One preferred cartridge interlock arrangement 100 is illustrated ingreater detail in FIGS. 9-11. The cartridge interlock arrangement 100depicted generally forms a cog construction 104 in order to cooperatewith compatible structure in the bowl 30. The cog construction 104includes at least one cog or tooth 106 extending from the outer surface102 of the second end cap 52. In preferred embodiments, the cogconstruction 104 includes at least two teeth 106 extending from theouter surface 102. In the particular embodiment illustrated, the cogconstruction 104 has 18 teeth 106. It is contemplated that manypreferred arrangements will include no more than 30 teeth and typically5-25 teeth. Each of the teeth 106 is oriented to engage the filter bowl30, when the filter cartridge 32 is mounted in the filter bowl 30 andthe bowl 30 is rotated in a direction to remove the bowl-cartridgefilter 24 from the filter head 22.

While a number of embodiments are contemplated, for the arrangementillustrated in FIGS. 9-12, each of the teeth 106 preferably includes afirst end flank 110, a second end flank 111, a heel 114, a toe 118, anda side flank 124. The first and second end flanks 110, 111 provide asurface 116 that accepts the rotary forces translated to it from thebowl 30. As such, each of the end flanks 110, 111 is constructed to havea surface area large enough to make meaningful contact with theinterlock arrangement on the bowl. In the one illustrated, each of theend flanks 110, 111 extends generally normal to the outer surface 102,but could vary between 80-100° relative to the outer surface 102.

Each of the teeth 106, in the illustrated embodiment, includes each ofthe first and second end flanks 110, 111 extending from the heel 114 tothe toe 118. Further, in the illustrated embodiment, each of the sideflanks 124 also extends from the heel 114 to the toe 118. Each of theside flanks 124 intersects each of the first and second end flanks 110,111 to define corners 125, 126. Each of the side flanks 124 is alsopreferably extending generally normal to the outer surface 102, butcould vary between 80-100′ relative to the outer surface 102.

Still in reference to FIG. 9, each of the toes 118 include at least afirst bevel surface 112 extending from one of the first and second endflanks 110, 111 and is preferably angled obliquely relative to therespective end flank 110, 111. In the particular embodiment illustrated,each of the toes 118 further includes a second bevel surface 113 thatextends from the other of the end flanks 110, 111 for each tooth 106 andis angled obliquely relative to that particular end flank 110, 111.

In reference now to FIG. 12, a fragmented, enlarged, side elevationalview of tooth 106 is shown. The angle of the first bevel surface 112relative to the first end flank 110 is shown at reference character α.Similarly, the angle which the second bevel surface 113 extends relativeto the second end flank 111 is shown by the reference character θ. Inpreferred arrangements, the angles α and θ are equal to each other. Inother embodiments, these angles may differ from each other. In theparticular embodiment illustrated, each of the angles α and θ is atleast 10°, no greater than 60°, and typically 20-45°. One preferredangle used for α and θ is 30°. Still in reference to FIG. 12, it can beseen that each of the bevel surfaces 112, 113 intersect and define acorner 128. The overall height of each tooth 106 from the heel 114 tothe corner 128, which represents the furthermost point from surface 102,is at least 2 mm, no greater than 100 mm, in many instances 3-20 mm, andin the particular illustrated embodiment, is 7 mm.

From reviewing FIGS. 9 and 12, it can be appreciated that each of theteeth 106, as depicted in the drawings, has the profile of a five-sidedpolygon. Another term to describe the shape is “house shaped.” By “houseshaped”, it is meant generally a rectangular profile with a triangularshape on top of the rectangle.

FIG. 11 depicts other features of this particular end cap 52. The endcap 52 depicted includes an outer surrounding wall 130 forming anannular portion 132 and an end wall 134 forming the axial surface 122.The end wall 134 defines a central opening 136 that allows the filtercartridge 32 to be mounted and dismounted over the center tube 34. Aninternal pair of rings 138, 140 define a cup 142 for holding andsupporting the media extension 48 therein. In preferred arrangements,the cup 142 helps to hold urethane potting material in order to securethe media 48 to the end cap 52.

In reference now to FIG. 10, it can be seen that in the particularembodiment illustrated, each of the teeth 106 is evenly spaced aroundthe opening 136. In the one shown, each tooth 106 is spaced at angle βrelative to an adjacent tooth 106, as centered along the corner 128.Angle β will vary based upon the number of teeth 106 that are desired.For three or fewer teeth, the angle β will be greater than 90°, but lessthan 180°. For the particular arrangement shown when there are eighteenteeth 106, the angle β is at least 5°, no greater than 40°, typically10-30°, and in the one shown is 20°.

Turning now to FIGS. 6-8, the portion of the cooperating interlockarrangement 80 on the bowl 30 is depicted as a bowl interlockarrangement generally at 150.

In the preferred embodiment illustrated, the bowl interlock arrangement150 is oriented within the interior 54 of the bowl 30 in a location thatresults in a mating, meshing, engaging, or interlocking with thecartridge interlock arrangement 100. As shown in FIGS. 6-8, the bowlinterlock arrangement 150 is located on the interior surface 46 of theclosed end 56 of the bowl 30.

The preferred bowl interlock arrangement 150 comprises a cogconstruction 152 having at least one tooth 154. In preferredarrangements, there will be at least a first and second tooth 154. Theparticular embodiment illustrated has 18 teeth 154 arranged in a circle,each of the teeth 154 being evenly spaced around the projection 72 alongthe bottom 156 of the bowl 30. In many preferred arrangements, therewill be no more than 30 teeth 154, and typically 5-25 teeth.

Each of the teeth 154 extends or projects in an axial direction from thebottom 156. This projection is to allow for the teeth 154 to engage theteeth 106 of the cartridge interlock arrangement 100. In manyembodiments, there is the same number of teeth 154 on the bowl interlockarrangement 150 as there are teeth 106 on the cartridge interlockarrangement 100. In other embodiments, there can be fewer or more teeth106 on the cartridge interlock arrangement 100 than on the bowlinterlock arrangement 150.

In the particular illustrated embodiment, each of the teeth 154 has thesame shape as each of the teeth 106. As such, each of the teeth 104 hasfirst and second end flanks 155, 156; a side flank 157; a heel 158; anda toe 159. The toe 159 includes a first bevel surface 160 and a secondbevel surface 161. In the particular embodiment illustrated, the firstand second bevel surfaces 160, 161 are angled relative to the end flanks155, 156 at the same angles α and β, as described above, with respect toFIG. 12.

FIG. 3 illustrates the interlock arrangement 80, including the cartridgeinterlock arrangement 100 and the bowl interlock arrangement 150 incooperative engagement. In particular, one of the end flanks 110, 111 ofthe cartridge interlock arrangement 100 engages one of the end flanks155, 156 of the bowl interlock arrangement 150 for each of the teeth 106and teeth 154. In this manner, when the bowl 30 is turned in a rotarymotion relative to the filter head 22 in order to threadably release thebowl 30 from the filter head 22, one of the end flanks 155, 156 of eachof the teeth 154 of the bowl 30 engages and urges against one of the endflanks 110, 111 of the teeth 106 of the cartridge interlock arrangement100. Thus, this translates the rotary force from the bowl 30 to thefilter cartridge 32. This helps to result in a filter cartridge 32 thatis removed with the bowl 30, when the bowl 30 is being removed from thefilter head 22.

The filtration system 20 is utilized as follows: The bowl-cartridgefilter 24 including the bowl 30 with the filter cartridge 32 operablyinstalled therein is mounted onto the filter head 22. This is done byrotating the bowl 30 relative to the filter head 22 in a manner tothreadably engage the bowl 30 to the filter head 22. Liquid to becleaned flows through the filter head 22, into the bowl-cartridge filter24, through the media 48 where particulates are trapped, out of thebowl-cartridge filter 24 into the filter head 22, and then out of thefilter head 22. After a period of use, the filter media 48 will becomeclogged or occluded. At this point, the bowl-cartridge filter 24 shouldbe serviced.

To service the bowl-cartridge filter 24, the bowl-cartridge filter 24 isrotated relative to the filter head in the opposite direction as it wasrotated to install it to unthread and release the bowl 30 from thefilter head. While the bowl 30 is rotated relative to the filter head,the cartridge filter 32 is simultaneously rotated with the filter head32 release the cartridge filter 32 from the filter head 22. This step ofsimultaneously rotating the filter cartridge 32 relative to the filterhead 22 includes using the interlock arrangement 150 on the bowl 30 tourge the interlock arrangement 100 that extends from the second end cap52 on the cartridge filter 32 in a rotary motion. In particular, one ofthe end flanks 155, 156 in each of the teeth 154 engages and pushesagainst one of the respective end flanks 110, 111 on a respective tooth106 on the cartridge interlock arrangement 100.

After the bowl-cartridge filter 24 has been removed from the filter head22, the filter cartridge 32 is removed from the bowl 30 by grasping thehandle member 92 and pulling the filter cartridge 32 out of the bowl 30through the opening 58. This act of pulling also releases the seal 62between the filter cartridge 32 and the bowl 30.

After the filter cartridge 32 has been removed from the bowl 30, thefilter cartridge 32 is discarded. In preferred arrangements, the filtercartridge 32 is constructed of at least 95%, and preferably 100%non-metallic materials. Non-metallic materials allows the filtercartridge 32 to be incinerated.

A new filter cartridge 32 is then installed within the bowl 30. This isdone by placing the filter cartridge 32 through the open end 58 of thebowl 30, and sliding it over the central core 34. The interlockarrangement 100 is aligned with the interlock arrangement 150, such thatthe cog construction 152 is oriented to mesh or engage with the cogconstruction 104. The seal 62 between the filter cartridge 32 and thebowl 30 is formed. This provides a refurbished bowl-cartridge filter 24,which may then be installed on the filter head 22.

C. The Arrangement of FIGS. 13-15

FIGS. 13-15 illustrate an alternate embodiment of cartridge interlockarrangement 100 on an end cap 200. In this particular embodiment, eachof the teeth 206 has the shape of a truncated A. As such, each of theteeth 206 includes a first end flank 208, a second end flank 209, a sideflank 210, and a toe 212. In the arrangement depicted, the toe 212 issmooth and curved, to bridge or connect first end flank 208 to thesecond end flank 209.

Each tooth 206 also includes a heel 214, which forms a bridge between anouter surface 213 and each of the first end flank 208, second end flank209, and side flank 210. In this instance, the heel 214 includes first,second, and third bevel surfaces 215, 216, and 217. The first bevelsurface 215 forms a transition between the outer surface 213 and thefirst end flank 208. Similarly, the second bevel surface 216 provides atransition between the outer surface 213 and the side flank 210.Finally, the third bevel surface 217 provides a transition between theouter surface 213 and the second end flank 209.

In reference to FIG. 14, it can be seen that in the particularembodiment illustrated, there are eighteen teeth 206. Each tooth 206 isgenerally evenly spaced about the center aperture 218, and evenly spacedbetween each respective tooth 206. The end cap 200 shown in FIGS. 13-15may be used to engage the filter bowl interlock arrangement 150 asdescribed herein. Alternatively, the end cap 200 may be used to engage afilter bowl interlock arrangement that has teeth shaped identically asteeth 206.

D. The Arrangement of FIGS. 16-21

In FIGS. 16-21, another alternative embodiment of the cartridgeinterlock arrangement 100 is illustrated utilizing an alternate end cap552. In this case, for the arrangement illustrated in FIGS. 16-18, eachof the teeth 506 preferably includes an end flank 510, a bevel surface512, and a heel 514. The end flank 510 provides a surface 516 that mayaccept the rotary forces translated to it from the bowl 30. As such, theend flank 510 is preferably constructed to have a surface area largeenough to make meaningful contact with the interlock arrangement on thebowl 30. In the one illustrated, the end flank 510 extends generallynormal to the outer surface 502, but could vary between 80-100 degreesrelative to the outer surface 502.

The end flank 510 defines a toe 518 at an end point of the end flank510. The bevel surface 512 preferably extends at least partially fromthe heel 514 to the toe 518. While the bevel surface 512 is depicted inthe drawings as being at an oblique angle with respect to the end flank510, it is contemplated that in other arrangements, the teeth 506 can berectangular in shape and have a non-angled surface 512.

In the arrangement depicted, the heel 514 is at the joint 520 (FIG. 17)where the tooth 506 and the outer surface 502 of the end cap 552intersect. The bevel surface 512 is angled obliquely with respect to theend flank 510 starting at the heel 514. In preferred arrangements, thebevel surface 512 is angled relative to the end flank 510 of at least 92degrees, no greater than 160 degrees, and usually 93-150 degrees. Inmany arrangements, this angle is 95-120 degrees. When measured relativeto the axial surface 522 of the second end cap 552, this angletranslates into the above-mentioned angles, minus 90 degrees; thus, atleast 2°, no greater than 70°, usually 3-60°, and in many arrangements,5-30°.

The depicted teeth 506 further include a pair of side flanks 524, 526extending from the outer surface 502 to the bevel surface 512, whichhelps provide structural support for the end flank 510. As can be seenin FIG. 16, the particular side flank 524 depicted has a generallytriangular shape, with a similar shape for the side flank 526. Further,in the particular embodiment depicted, each of the teeth 506 furtherdefines a land 528 extending from the bevel surface 512 to the toe 518and the end flank 510. The land 528 helps to provide a transitionbetween the end flank 510 and the bevel surface 512 and avoid sharpcorners or other projections, which may damage other components of thebowl cartridge filter 24.

From reviewing FIG. 16, it can be appreciated that each of the teeth 506as depicted has the general appearance of a pie wedge. Each of the piewedges in the form of the teeth 506 projects or extends outwardly in anaxial direction from the axial surface 522 of the outer surface 502 ofthe second end cap 552.

FIG. 18 depicts other features of this particular end cap 552. The endcap 552 depicted includes an outer surrounding wall 530 forming anannular portion 532 and an end wall 534 forming the axial surface 522.The end wall 534 defines a central opening 536 that allows the filtercartridge 32 to be mounted and dismounted over the center tube 34. Aninternal pair of rings 538, 540 define a cup 542 for holding andsupporting the media extension 48 therein. In preferred arrangements,the cup 542 helps to hold urethane potting material in order to securethe media 48 to the end cap 552. In the embodiment depicted, each of theteeth 506 is evenly spaced around the opening 536. Each of the teethextends at least 2 mm, no greater than 20 mm, and preferably 3-5 mm fromthe axial surface 522. This will generally correspond with the overallheight of the end flank 510.

FIG. 19 shows the filter cartridge 32 in exploded, perspective view,with the alternate end cap 552. Other than the alternate end cap 552,the filter cartridge 32 is the same as described above with respect toFIG. 4.

FIGS. 20 and 21 illustrate the bowl 630 and including an alternate bowlinterlock arrangement 150, configured to mate, engage, or mesh with thealternate interlock arrangement for end cap 552. The interlockarrangement 150 of the bowl 630 includes a plurality of teeth 664, whichare shaped complimentary and analogously as the teeth 506 for the endcap 552. As such, each of the teeth 664 includes an end flank 668, abevel surface 660, a heel 662, a toe 664, a pair of side flanks 666,668, and a top land 670.

Each of the teeth 664 extends from the bottom surface 656 of the bowl640 far enough to engage and mesh with the interlock arrangement 100 onthe end cap 552. As can be seen in FIG. 20, each of the teeth 654 isevenly spaced around the projection 672. Each of the teeth 654 extendsat least 2 mm, no greater than 20 mm, and in many instances, 3-5 mm fromthe bottom surface 656. This generally corresponds to the overall heightof the end flank 658.

E. The Arrangement of FIGS. 22-31

FIGS. 22-31 illustrate another embodiment of a bowl-cartridge filter.The bowl-cartridge filter is analogous to the arrangements describedabove in that it includes a filter cartridge 302 that is removeable andreplaceable within a bowl 304 (FIGS. 28-30).

In reference first to FIG. 22, the particular filter cartridge 302illustrated includes an extension of filter media 305 extending betweena first end cap 306 and a second end cap 308. The filter media 305 issupported by an inner support tube or inner liner 310. The cartridgefilter 302 includes an O-ring 312 mounted within an opening 314 in thefirst end cap 306 to create a seal with the filter head 22, as describedabove in connection with the embodiment of FIGS. 1-12.

The end cap 308 depicted includes an outer surrounding wall 318 formingan annular portion 320 and an end wall 322 forming an axial surface 324.The end wall 322, in this embodiment, is solid, non-porous, to form aclosed surface 326. The closed surface 326 defines vanes 328 to providestrength to the end cap 308. There is also a projection 330 extendingfrom the end wall 322 in a direction toward the first end cap 306, whichfunctions to provide internal strength to the filter cartridge 302.

As with the above embodiments, the bowl-cartridge filter of FIGS. 22-31includes cooperative interlock arrangement 80 to help insure the removalof the filter cartridge 302 from the filter head 22 at the same time thebowl 304 is removed from the filter head 22. The filter cartridge 302includes interlock arrangement 100, which forms part of the cooperativeinterlock arrangement 80 between the cartridge 302 and the bowl 304. Inthe embodiment of FIGS. 22-31, the cartridge interlock arrangement 100extends from outer surface 316 of the second end cap 308. In particular,the interlock arrangement 100 extends from the annular portion 320.

As with the above embodiments, the cartridge interlock arrangement 100depicted forms cog construction 104 in order to cooperate withcompatible structure in the bowl 304. The cog construction 104 includesat least one cog or tooth 332 extending from the outer surface 316 ofthe second end cap 308. In this particular embodiment, each of the teeth332 extends from the annular portion 320 of the outer surface 316 of thesecond end cap 308. As with the embodiment of FIGS. 1-12, the teeth 332in this embodiment are illustrated as having the profile of a five-sidedpolygon. In other words, the shape is “house shaped.” It should beappreciated that other shapes of the teeth 332 can be used, includingthe shapes described in connection with FIGS. 13-21.

Each of the teeth 332 has a first end flank 334, a second end flank 336,a side flank 338, a heel 340, and a toe 342. The first and second endflanks 334, 336 extending from the heel 340 to the toe 342. The sideflank extends from the heel 340 to the toe 342 and intersects each ofthe first and second end flanks 334, 336. The toe 342 includes a firstbevel surface 344 extending from the first end flank 334 and beingangled obliquely relative to the first end flank 334. The toe 342 alsoincludes a second bevel surface 346 extending from and being angledobliquely relative to the second end flank 336.

In FIG. 26, there is illustrated the angles 348, 350 of the first bevelsurface 344 relative to the first end flank 334 and the second bevelsurface 346 relative to the second end flank 336. In preferredarrangements, the angles 348, 350 are equal to each other. In otherembodiments, these angles may differ from each other. In the particularembodiment illustrated, each of the angles 348, 350 is at least 10°, nogreater than 60°, and typically 20°-45°. One preferred angle used forangles 348 and 350 is 30°. Still in reference to FIG. 26, it can be seenthat each of the bevel surfaces 344, 346 intersects and defines thecorner 352. The overall height of each tooth 332 from the heel 340 tothe corner 352 is at least 2 mm, no greater than 100 mm, in manyinstances 3-20 mm, and in the particular example, is 9 mm.

In FIG. 25, it can be seen that in the particular embodimentillustrated, there are at least two teeth 332, preferably at least threeteeth 332, and in the one shown, there are four teeth 332. Each of theteeth 332 is evenly spaced around the annular portion 320. For theexample shown, there is an angle of 90° between each of the teeth 332.

Turning now to FIGS. 29-31, the portion of the cooperating interlockarrangement 80 on the bowl 304 is depicted as bowl interlock arrangementgenerally at 150. As with the above embodiments, the preferred bowlinterlock arrangement 150 comprises cog construction 152 having at leastone tooth 360. In preferred arrangements, there will be at least a firstand a second tooth 360. The particular embodiment illustrated as fourteeth 360 arrangement in a circle, each of the teeth 360 being evenlyspaced around the projection 362 along the bottom 364 of the bowl 304.The projection 362 engages and is received within the recess 329 (FIG.22) defined by the second end cap 308.

Each of the teeth 360 extends or projects in an axial direction from aninternal surface 366 of a side wall 368 of the bowl 304. Thisarrangement allows the teeth 360 to engage the teeth 332 of thecartridge interlock arrangement 100. In many embodiments, there is thesame number of teeth 360 as teeth 332. In other embodiments, there canbe fewer or more teeth on the cartridge interlock arrangement 100 thanon the bowl interlock arrangement 150.

In the particular illustrated embodiment in FIG. 31, each of the teeth360 has the same shape as each of the teeth 332. As such, each of theteeth 360 has first and second end flanks 370, 371; a side flank 372; aheel 373; and a toe 374. The toe 374 includes a first bevel surface 375and a second bevel surface 376. The first and second bevel surfaces 375,376 are angled relative to the end flanks 370, 371 at the same angles348, 350 as described above with respective to FIG. 26.

1-20. (canceled)
 21. A bowl-cartridge filter arrangement configured foroperable installation onto a filter head by rotation in a firstdirection and removal from the filter head by rotation in an opposite,second direction; the bowl-cartridge filter arrangement comprising: (a)a filter bowl having an interior surface; said filter bowl including afilter bowl interlock arrangement extending from said filter bowlinterior surface; (i) said filter bowl interlock arrangement includingat least three teeth; (ii) said bowl includes an open end and a closedend; said filter bowl interlock arrangement extending from said interiorsurface of said closed end; (b) a disposable cartridge filter operablymounted in and selectively removable from the bowl; the filter cartridgecomprising: (i) an extension of filter media; said extension having afirst end and an opposite second end; (ii) a first end cap secured tosaid extension of filter media at said first end; and (iii) a second endcap secured to said extension of filter media at said second end; (A)the second end cap including a solid, non-porous end wall defining aclosed surface; (B) the second end cap including a projection extendingfrom the end wall in a direction toward the first end cap; (C) thesecond end cap including a filter cartridge interlock arrangement; (1)the filter cartridge interlock arrangement engaging said three teeth ofsaid filter bowl interlock arrangement.
 22. A bowl-cartridge filterarrangement according to claim 21 wherein: (a) said filter cartridgeinterlock arrangement includes at least three teeth extending from saidsecond end cap; (i) said three teeth of said filter cartridge interlockarrangement engaging said three tooth of said filter bowl interlockarrangement.
 23. A bowl-cartridge filter arrangement according to claim21 wherein: (a) said bowl includes a threaded region adjacent to saidopen end for releasable attachment to a filter head.
 24. Abowl-cartridge filter arrangement according to claim 22 wherein: (a)said three teeth of said filter cartridge interlock arrangement extendfrom an outer surrounding wall of the second end cap.
 25. A method ofservicing a bowl-cartridge filter operably installed on a filter head;the bowl-cartridge filter including a bowl and a cartridge filterselectively removable from the bowl; the cartridge filter including anextension of filter media between first and second opposite end caps;the method including: (a) rotating the bowl relative to the filter headto release the bowl from the filter head; (b) while rotating the bowlrelative to the filter head, simultaneously rotating the cartridgefilter relative to the filter head; (i) wherein the step ofsimultaneously rotating the cartridge filter relative to filter headincludes using an interlock arrangement on the bowl to urge an interlockarrangement on the cartridge filter in a rotary motion; (A) the bowlinterlock arrangement including at least three teeth; (B) the bowlincludes an open end and a closed end; the filter bowl interlockarrangement extending from the interior surface of said closed end; (C)the cartridge filter including first and second opposite end caps; (1)the second end cap including a solid, non-porous end wall defining aclosed surface; (2) the second end cap including a projection extendingfrom the end wall in a direction toward the first end cap; and (C) thesecond end cap including the cartridge filter interlock arrangement. 26.A method according to claim 25 wherein: (a) the cartridge filterinterlock arrangement includes at least three teeth extending from thesecond end cap; (b) said step of simultaneously rotating includesengaging the three teeth of the filter cartridge interlock arrangementagainst the three teeth of the filter bowl interlock arrangement.
 27. Amethod according to claim 26 wherein: (a) the step of rotating the bowlrelative to the filter head to release the bowl from the filter headincludes releasing a threaded region adjacent to the open end of thebowl from the filter head.
 28. A method according to claim 26 wherein:(a) the at least three teeth of the filter cartridge interlockarrangement includes at least three teeth extending from an outersurrounding wall of the second end cap; and (b) said step ofsimultaneously rotating includes engaging the at least three teeth ofthe filter cartridge interlock arrangement extending from the outersurrounding wall of the second cap against the three teeth of the filterbowl interlock arrangement.
 29. A filter cartridge for use in abowl-cartridge filter; the bowl-cartridge filter configured for operableinstallation onto a filter head by rotation in a first direction andremoval from the filter head by rotation in an opposite, seconddirection; the bowl-cartridge filter including a bowl and a cartridgefilter for selective mounting in and removal from the bowl; the filtercartridge comprising: (a) an extension of filter media; said extensionhaving a first end and an opposite second end; (b) a first end capsecured to said extension of filter media at said first end; and (c) asecond end cap secured to said extension of filter media at said secondend; (ii) the second end cap defining a central portion adapted toreceive a projection from a bowl; and (iii) the second end cap includinga filter cartridge interlock arrangement including a plurality of spacesopen to vertical motion adapted to receive a plurality of projectionsfrom a bowl through vertical engagement, when the filter cartridge isoperably positioned in a bowl.
 30. A filter cartridge according to claim29 wherein: (a) the filter cartridge interlock arrangement furtherincludes a plurality of teeth; each tooth of said plurality of teethbeing spaced apart by a respective one of said spaces of the pluralityof spaces.
 31. A filter cartridge according to claim 29 wherein: (a) theplurality of spaces circumscribed the central portion of the second endcap.
 32. A filter cartridge according to claim 29 wherein: (a) theextension of filter media comprises cellulose.